fast radio bursts - 2023 ACF Nationals

Question

These phenomena were at one time speculated to be artificial because similar signals called perytons were shown to be caused by a microwave. For 10 points each:

[10h] Name these phenomena whose distribution can be analyzed by plotting them on graphs of fluence versus dispersion measure. Many of them have been observed with the CHIME (“chime”) telescope.

ANSWER: fast radio bursts [or FRBs] (Perytons are named after the mythological creature from Jorge Luis Borges’s Book of Imaginary Beings.)

[10m] A crude rule of thumb calculates this quantity for a fast radio burst by dividing its dispersion measure by 1,000. Surveys of this quantity, such as the one carried out by the SDSS, measure it to map the large-scale structures of galaxies.

ANSWER: redshift [accept cosmological redshift or photometric redshift; reject “Doppler redshift” or “Doppler shift” or “blueshift”]

[10e] The first fast radio burst was detected in a survey of these objects that were discovered by Jocelyn Bell Burnell. They are neutron stars that emit radio waves at regular periods.

ANSWER: pulsars [accept pulsating radio sources]

Back to bonuses

Summary


2023 ACF Nationals	04/22/2023	Y	20	13.50	95%	20%	20%

Data


Northwestern A	Claremont A	0	0	10	10
Cornell A	Imperial A	0	10	10	20
Yale B	WUSTL A	0	0	10	10
Chicago B	Iowa State A	10	10	10	30
MIT A	Chicago C	0	0	10	10
Columbia B	Purdue A	0	10	10	20
Florida A	South Carolina A	10	0	10	20
NYU A	Georgia Tech B	0	0	0	0
Virginia A	Johns Hopkins A	0	0	10	10
Chicago A	Minnesota A	0	0	10	10
Texas A	Ohio State A	10	0	10	20
Florida B	Penn State A	0	0	10	10
Rutgers A	Harvard A	0	0	10	10
WUSTL B	Rutgers B	0	0	10	10
Vanderbilt A	Houston A	0	0	10	10
Cornell B	Stanford A	0	0	10	10
Georgia Tech A	Illinois A	0	10	10	20
Duke A	Michigan A	0	0	10	10
Indiana A	Toronto A	10	0	10	20
UC Berkeley B	McGill A	0	0	10	10